America



Dec. 11, 1928. 1,695,239

A. B. 'NoRT'oN METHOD OF PREVENTING WARPAGE OF CASTINGS IN COOLING Filed Aug. 4,1926

NV T R '1 v u 7 BY TTORNEYS Patented D' 11,1928.

UNITED STATES- 1,e95,z39 I L EN B. NORTON, or cLEvriLAND, OHIO, ASSIGNOR TO ALUMINUMOOMPANY or AMERICA, or PITTSBURGH, PENNSYLVANIA, A CORPORATION or PENNSYLVANIA.

METHOD OF PREVENTING WAR PAGE OF CAQTINGS IN COOLING.

Application filed August 4, 1926. Serial No. 126,979.

This invention relates to the production of straight, unwarped castings, and more par.-

-ticularly to. a method of and apparatus for controlling the shape of castings.

An object of the invention is to provide a method and means which will be efficient, effective, and economical in producing castings of'a desired shape. i

Other objects will hereinafter appear.

The invention will be better understood fromthe explanation of one practical embodiment of the apparatus and description of the method as practiced therewith.

In the accompanyin is a perspective view'o? one form of apparatus for preventing warping of ironer shoe castings made of aluminum alloy. These castings are made of an alloy which possesses very little ductility when it has cooled. The castings are true when removed from the molds but warp during cooling. Due to the lack of ductility they cannot be satisfactorily'straightened after cooling.

\ When such a castin is removed from the mold at a relatively hlgh temperature it can be easily deformed to a moderate extent. If

a it is immediately deformed and restrained.

in the deformed position or if it is merely clamped so as to hold the form it had when it came from the mold, it will on cooling retain the form in which it was restrained during the cooling process and after cooll-supported by legs 2 ,and upon which the shoe-casting. 3 is clamped, The clamping means consist of blocks 4 which are pressed lfiion the shoe by handpperated screws 5.

e screws are threaded through bars 6 which are detachabl held to the bed by cap screws 7 having'hea(i8.* f In practice a 'w'ei ht 9 has been placed on the'central part of the shoe casting, although clamping means similar to'those' used at the ends-of theshoe might be substituted therefor. Shims 10 may be inserted between the casting and the bed. to give the casting slight curvature as a compensation" for any flexure occurring when the casting is released from'the clamping means, or: in y drawing, the figure I The operation of the apparatus'is as ifo1- lows: A'casting is made and taken directly from the mold to the bed while still at an elevated temperature. The clamps are-immediately tightened and the weight placed upon the casting so that it is held firmly upon the bed. The casting is now left to cool, after which it is removed. It will then retain its shape under atmospheric temperature and is not permanently distorted by subjection -to. the normal operating temperature.

While in the example above set forth-the apparatus and method have been described as being applied toa casting which itis desired to maintain straight upon cooling or to give only a slight curvature, it will be obvious that they may be applied to castings ofvarious articles which are cast. in one form and, after being-removed from the mold, are bent to some other form.

'For instance, a casting might be formed in a mold without the curvature which is desired in the finished article, if this weredeis placed upon a table or form, suitable arrangements of weights, clamps. etc. would shape the casting to the desired form and retain it in this shape while it cools. Due

to the freedom of movement of the particles 7 of the metal in their hot'state, these would readjust themselves and relieve any internal stresses that would ordinarily be set up during cooling of the casting.

' Again, some types of casting might be more conveniently cast in a curved shape and bent or straightened thereafter to the form dcsired in the finishedarticle.

While-I have describedone particular form of apparatus,'it will be readily apparent that many modifications and variations thereof may be'made, and, in fact, must be made for diiferently shaped castings, and I do not therefore limit myself to the precise details shown but claim broadly the method and apparatus by which it. may be performed, claiming all equivalent methods and structures which come within the scope of the ap pendedclaims. 4

. I claim:

1. The method of alloy castings, which comprises the hot castings directl from the molds, placing them ing the casting to a desired shape, and thereupon a sur ace of the desired configuration, after restrainmg the movement of parts of clamping them to said surface, and allowing the casting during cooling.

them to cool While so clamped. r In testimony whereof I hereunto aifix my 5 2. The process "of treating aluminum a1-' signature this 20th day of July. 1926.

10y castings which comprises taking the casting directly from its mold while hot, bend- 1 ALLEN B. NORTON. 

